1. Technical Field
The present invention relates to a method of manufacturing a colored lens of plastic or glass, which is used for glasses and so on.
2. Related Art
Instead of dyeing a plastic lens or a glass lens constituting a substrate, it is known to dye a functional layer of a colored lens, for example, a hard coat layer which is stacked on a substrate. Colored lenses are generally used as a lens for vision correction or a spectacle lens such as sunglasses and so on. JP-A-11-310755 discloses a method including the steps of applying a hard coat liquid onto the convex surface of a spectacle lens, curing the liquid by heating at a temperature of 135° C. for 0.5 hours, applying a hard coat liquid onto the concave surface of the spectacle lens, curing the liquid by heating at a temperature of 135° C. for 2.5 hours, and dipping the lens having a hard coat layer thereon in a dyeing liquid to be dyed.
Reduction in dyeing time and total manufacturing time is an important goal in manufacturing a colored lens.
In known methods of manufacturing a colored lens, a coating liquid for forming a dyeable hard coat layer is applied onto a lens substrate, a hard coat layer is heated so as to be completely cured (in a hardened state with burning), and then the lens substrate having the hard coat layer formed thereon is dyed by a dip dyeing method. As a result of extensive and intensive studies for dyed lenses, it has been determined that it is desirable to perform an annealing process for about one hour after a dyeing process in order to prevent uneven coloring from occurring and to fix a color. Then it is desirable to form an anti-reflection layer and the like if necessary. However, the annealing process after the dyeing process increases total manufacturing time.